1. Field of the Invention
The invention relates to a scanning unit.
2. Description of the Related Art
Scanning units are being used to either determine the presence of an object at a particular position or in a particular area, or to determine the distance between two objects which can be variable.
Scanning units are often operated through optical or electronic methods, wherein each method has its specific pros and cons.
In particular when a scanning unit has to be operated under harsh environmental conditions, thus in a highly contaminated environment or in an environment loaded with abrasive solid particles under high pressure, great heat or high humidity, optical and purely electronic scanning units reach their limits, in particular since their tight long term encapsulation poses considerable problems.